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This is a copy of the slides presented at the meeting but not formally written up for the volume.
We have studied the effects of epitaxial strains on structural phase transition behavior of fully-commensurate single crystal thin films of SrRuO3 using in situ temperature-dependent reflection high-energy electron diffraction (RHEED) and ex situ temperature-dependent x-ray diffraction (XRD) measurements. From RHEED measurements on compressively-strained (110) SrRuO3 grown on (001) SrTiO3 substrate, it was found that the surface of SrRuO3 showed no orthorhombic distortion even at room temperature (25°C) below the thickness of 10 monolayers (MLs). The orthorhombic transition temperature (TC) was determined to be 90°C at the thickness of 13 ML;s and then systematically increased up to 238°C at 35 ML. More interestingly, however, tensilely-strained SrRuO3 films grown on (110) DyScO3 and (110) GdScO3 substrates have simple cubic perovskite structure at room temperature irrespectively of SrRuO3 thicknesses. The shift of TC is very dramatic, considering that the orthorhombic transition temperature of SrRuO3 is known to be 547°C in bulk form. These unique transition behaviors were also confirmed by temperature-dependent four-circle x-ray diffraction measurements. TC of 35 ML thick SrRuO3 on SrTiO3 were determined to be 250°C and which was consistent with that determined from RHEED measurements.
Among young Samoan children, diet may not be optimal: in 2015, 16·1 % of 24–59-month-olds were overweight/obese, 20·3 % stunted and 34·1 % anaemic. The present study aimed to identify dietary patterns among 24–59-month-old Samoan children and evaluate their association with: (i) child, maternal and household characteristics; and (ii) nutritional status indicators (stunting, overweight/obesity, anaemia).
A community-based, cross-sectional study. Principal component analysis on 117 FFQ items was used to identify empirical dietary patterns. Distributions of child, maternal and household characteristics were examined by factor score quintiles. The regression of nutritional status indicators v. these quintiles was performed using logistic regression models.
Ten villages on the Samoan island of Upolu.
A convenience sample of mother–child pairs (n 305).
Two dietary patterns, modern and neo-traditional, emerged. The modern pattern was loaded with ‘westernized’ foods (red meat, condiments and snacks). The neo-traditional pattern included vegetables, local starches, coconuts, fish and poultry. Following the modern diet was associated with urban residence, greater maternal educational attainment, higher socio-economic status, lower vitamin C intake and higher sugar intake. Following the neo-traditional diet was associated with rural residence, lower socio-economic status, higher vitamin C intake and lower sugar intake. While dietary patterns were not related to stunting or anaemia, following the neo-traditional pattern was positively associated with child overweight/obesity (adjusted OR=4·23, 95 % CI 1·26, 14·17, for the highest quintile, P-trend=0·06).
Further longitudinal monitoring and evaluation of early childhood growth and development are needed to understand the influences of early diet on child health in Samoa.
Young children are particularly vulnerable to malnutrition as nutrition transition progresses. The present study aimed to document the prevalence, coexistence and correlates of nutritional status (stunting, overweight/obesity and anaemia) in Samoan children aged 24–59 months.
A cross-sectional community-based survey. Height and weight were used to determine prevalence of stunting (height-for-age Z-score <−2) and overweight/obesity (BMI-for-age Z-score >+2) based on WHO growth standards. Anaemia was determined using an AimStrip Hemoglobin test system (Hb <110 g/l).
Ten villages on the Samoan island of Upolu.
Mother–child pairs (n 305) recruited using convenience sampling.
Moderate or severe stunting was apparent in 20·3 % of children, 16·1 % were overweight/obese and 34·1 % were anaemic. Among the overweight/obese children, 28·6 % were also stunted and 42·9 % anaemic, indicating dual burden of malnutrition. Stunting was significantly less likely among girls (OR=0·41; 95 % CI 0·21, 0·79, P<0·01) than boys. Overweight/obesity was associated with higher family socio-economic status and decreased sugar intake (OR per 10 g/d=0·89, 95 % CI 0·80, 0·99, P=0·032). The odds of anaemia decreased with age and anaemia was more likely in children with an anaemic mother (OR=2·20; 95 % CI 1·22, 3·98, P=0·007). No child, maternal or household characteristic was associated with more than one of the nutritional status outcomes, highlighting the need for condition-specific interventions in this age group.
The observed prevalences of stunting, overweight/obesity and anaemia suggest that it is critical to invest in nutrition and develop health programmes targeting early childhood growth and development in Samoa.
Almost nothing is known about the potential negative effects of Internet-based psychological treatments for depression. This study aims at investigating deterioration and its moderators within randomized trials on Internet-based guided self-help for adult depression, using an individual patient data meta-analyses (IPDMA) approach.
Studies were identified through systematic searches (PubMed, PsycINFO, EMBASE, Cochrane Library). Deterioration in participants was defined as a significant symptom increase according to the reliable change index (i.e. 7.68 points in the CES-D; 7.63 points in the BDI). Two-step IPDMA procedures, with a random-effects model were used to pool data.
A total of 18 studies (21 comparisons, 2079 participants) contributed data to the analysis. The risk for a reliable deterioration from baseline to post-treatment was significantly lower in the intervention v. control conditions (3.36 v. 7.60; relative risk 0.47, 95% confidence interval 0.29–0.75). Education moderated effects on deterioration, with patients with low education displaying a higher risk for deterioration than patients with higher education. Deterioration rates for patients with low education did not differ statistically significantly between intervention and control groups. The benefit–risk ratio for patients with low education indicated that 9.38 patients achieve a treatment response for each patient experiencing a symptom deterioration.
Internet-based guided self-help is associated with a mean reduced risk for a symptom deterioration compared to controls. Treatment and symptom progress of patients with low education should be closely monitored, as some patients might face an increased risk for symptom deterioration. Future studies should examine predictors of deterioration in patients with low education.
Gilliland et al. (2000) have reported HST photometric observations of 34000 stars in the globular cluster 47 Tuc, showing an absence of close-in giant planets in that cluster relative to their frequency in the solar neighborhood. Here we describe the methods of time-series analysis that were used to search the 47 Tuc data for transits by giant extrasolar planets, and the means by which these methods were validated.
The role of routine intra-operative parathyroid hormone monitoring for sporadic primary hyperparathyroidism is contentious. Satisfactory results can be achieved in high-volume centres. The results of low-volume hospitals are rarely studied.
A retrospective, non-comparative study was conducted. From November 2002 to October 2012, 105 patients with clinically sporadic primary hyperparathyroidism underwent focused parathyroidectomy without intra-operative parathyroid hormone monitoring. Single adenoma was localised on pre-operative ultrasonography or sestamibi scan. The cure rate, surgical complication rate and pathology findings were evaluated.
Most of the operations (63.8 per cent) were performed under local anaesthesia. All but two patients (98.1 per cent) were cured after surgery. There was only one case of double adenomas. No recurrent hyperparathyroidism was observed after a mean follow up of 56.9 months. Surgical complications comprised two cases (1.9 per cent) of transient vocal fold palsy and one case (1.0 per cent) of permanent vocal fold palsy. Seven patients (6.7 per cent) suffered temporary hypocalcaemia.
Satisfactory results of focused parathyroidectomy without routine intra-operative parathyroid hormone monitoring for appropriately selected primary hyperparathyroidism cases can be attained in a low-volume hospital.
Individuals with borderline personality disorder (BPD) frequently display co-morbid mental disorders. These disorders include ‘internalizing’ disorders (such as major depressive disorder and anxiety disorders) and ‘externalizing’ disorders (such as substance use disorders and antisocial personality disorder). It is hypothesized that these disorders may arise from latent ‘internalizing’ and ‘externalizing’ liability factors. Factor analytic studies suggest that internalizing and externalizing factors both contribute to BPD, but the extent to which such contributions are familial is unknown.
Participants were 368 probands (132 with BPD; 134 without BPD; and 102 with major depressive disorder) and 885 siblings and parents of probands. Participants were administered the Diagnostic Interview for DSM-IV Personality Disorders, the Revised Diagnostic Interview for Borderlines, and the Structured Clinical Interview for DSM-IV.
On confirmatory factor analysis of within-person associations of disorders, BPD loaded moderately on internalizing (factor loading 0.53, s.e. = 0.10, p < 0.001) and externalizing latent variables (0.48, s.e. = 0.10, p < 0.001). Within-family associations were assessed using structural equation models of familial and non-familial factors for BPD, internalizing disorders, and externalizing disorders. In a Cholesky decomposition model, 84% (s.e. = 17%, p < 0.001) of the association of BPD with internalizing and externalizing factors was accounted for by familial contributions.
Familial internalizing and externalizing liability factors are both associated with, and therefore may mutually contribute to, BPD. These familial contributions account largely for the pattern of co-morbidity between BPD and internalizing and externalizing disorders.
Carefully timed tandem microbubbles have been shown to produce directional and targeted membrane poration of individual cells in microfluidic systems, which could be of use in ultrasound-mediated drug and gene delivery. This study aims at contributing to the understanding of the mechanisms at play in such an interaction. The dynamics of single and tandem microbubbles between two parallel plates is studied numerically and analytically. Comparisons are then made between the numerical results and the available experimental results. Numerically, assuming a potential flow, a three-dimensional boundary element method (BEM) is used to describe complex bubble deformations, jet formation, and bubble splitting. Analytically, compressibility and viscous boundary layer effects along the channel walls, neglected in the BEM model, are considered while shape of the bubble is not considered. Comparisons show that energy losses modify the bubble dynamics when the two approaches use identical initial conditions. The initial conditions in the boundary element method can be adjusted to recover the bubble period and maximum bubble volume when in an infinite medium. Using the same conditions enables the method to recover the full dynamics of single and tandem bubbles, including large deformations and fast re-entering jet formation. This method can be used as a design tool for future tandem-bubble sonoporation experiments.
The passive film stability of several Fe-based amorphous metal formulations have been found to be comparable to that of high-performance Ni-based alloys, and superior to that of stainless steels, based on electrochemical measurements of the passive film breakdown potential and general corrosion rates. Chromium (Cr), molybdenum (Mo) and tungsten (W) provide corrosion resistance; boron (B) enables glass formation; and rare earths such as yttrium (Y) lower critical cooling rate (CCR). The high boron content of this particular amorphous metal also makes it an effective neutron absorber, and suitable for criticality control applications, as discussed in companion publications. Corrosion data for SAM2X5 (Fe49.7Cr17.7Mn1.9Mo7.4W1.6B15.2C3.8Si2.4) is discussed here.
Background: The Consortium to Establish a Registry for Alzheimer's Disease Neuropsychological Assessment Battery (CERAD-NAB) offers information on the clinical diagnosis of Alzheimer's disease (AD) and gives a profile of cognitive functioning. This study explores the effects of age, education and gender on participants' performance on eight subtests in the Chinese-Cantonese version of the CERAD-NAB.
Methods: The original English version of the CERAD-NAB was translated and content-validated into a Chinese-Cantonese version to suit the Hong Kong Chinese population. The battery was administered to 187 healthy volunteers aged 60 to 94 years. Participants were excluded if they had neurological, medical or psychiatric disorders (including dementia). Stepwise multiple linear regression analyses were performed to assess the relative contribution of the demographic variables to the scores on each subtest.
Results: The Cantonese version of CERAD-NAB was shown to have good content validity and excellent inter-rater reliability. Stepwise multiple regression analyses revealed that performances on seven and four out of eight subtests in the CERAD-NAB were significantly influenced by education level and age, respectively. Age and education had significant effects on participants' performance on many tests. Gender also showed a significant effect on one subtest.
Conclusions: The preliminary data will serve as an initial phase for clinical interpretation of the CERAD-NAB for Cantonese-speaking Chinese elders.
We present results of an oxidation study of a-Si1−xCx:H films prepared by the plasma enhanced chemical vapor deposition of silane and acetylene. The composition (i.e. x) of the samples was determined by the flow rates of silane and acetylene. Oxidation was carried out at 400 to 850°C in dry oxygen ambient. The infrared (IR) spectra of the as-prepared films showed the intensity of the Si-C peak decreases and the Si-CH3 peak increases as x increases. The Si-H peak shifts to higher frequency as x increases. Note that the incorporation of CH3 radicals in a-Si1−xCx:H films has shown to introduce voids and increased the porosity of the films. The IR spectra of the oxidized samples showed clear Si-O stretching and rocking/wagging modes for all films. We suggest that the growth of oxide on a-Si1−xCx:H is a result of voids that facilitate the diffusion of oxidants into the film. We shown that the activation energy, obtained from the linear rate region of the oxide growth, was far less than the dissociation energies of the Si-Si, Si-C and Si-H bonds. We suggest that this could be due to the amorphous nature of the samples that caused the various chemical bonds to be weaker during oxidation.
We have investigated the structural and electrical properties of as-prepared and rapid thermal oxynitride films on C+ implanted solid phase epitaxially grown SiC. The oxynitride was grown using N2O. The C concentration of the samples was estimated to be 1, 2 and 5 at. %. From the infrared spectra, samples with 1 and 2 at. % carbon showed that the carbon was substitutionally incorporated into the silicon. No precipitation of SiC was detected. However, for the 5 at. % C sample, some precipitation was observed as indicated by a broad peak at ∼800 cm−1. The oxynitride films showed the Si-O-Si stretching mode at ∼1100 cm−1. The shoulder at 980–1067 cm−1 was due to the O-Si-N bond. The peak at 830 cm−1 was due to the Si-N and Si-C bonds and C-O complex vibrational mode was observed at 663 cm−1. Electrical characterization of the oxynitride films was carried out using the MOS capacitor structure. The interface state density was found to range between 5.7×1011 to 3.35×1012 cm−2eV−1 and increased with an increase in the C concentration. The electrical breakdown field was found to be in the range of 5–7 MV cm−1 and reduced with an increase in C concentration. The charge-to-breakdown value was measured and decreased with an increase in C concentration.
The median-times-to-failure (t50's) for straight
dual-damascene via-terminated copper interconnect structures, tested under
the same conditions, depend on whether the vias connect down to underlaying
leads (metal 2, M2, or via-below structures) or connect up to overlaying
leads (metal 1, M1, or via-above structures). Experimental results for a
variety of line lengths, widths, and numbers of vias show higher t50's for
M2 structures than for analogous M1 structures. It has been shown that
despite this asymmetry in lifetimes, the electromigration drift velocity is
the same for these two types of structures, suggesting that fatal void
volumes are different in these two cases. A numerical simulation tool based
on the Korhonen model has been developed and used to simulate the conditions
for void growth and correlate fatal void sizes with lifetimes. These
simulations suggest that the average fatal void size for M2 structures is
more than twice the size of that of M1 structures. This result supports an
earlier suggestion that preferential nucleation at the
Cu/Si3N4 interface in both M1 and M2 structures
leads to different fatal void sizes, because larger voids are required to
span the line thickness in M2 structures while smaller voids below the base
of vias can cause failures in M1 structures. However, it is also found that
the fatal void sizes corresponding to the shortest-times-to-failure (STTF's)
are similar for M1 and M2, suggesting that the voids that lead to the
shortest lifetimes occur at or in the vias in both cases, where a void need
only span the via to cause failure. Correlation of lifetimes and critical
void volumes provides a useful tool for distinguishing failure
Nano-sized Fe particles were synthesized by Chemical Vapor Condensation (CVC) Process using the precursor of iron carbonyl (Fe(CO)5) as the source. We investigated the microstructures, magnetic properties of the Fe nanoparticles and their oxidation behavior during annealing systematically by means of HRTEM, DTA-TG, Mössbauer spectroscopy. The prepared particle was nearly spherical shape and core-shell type structure. The magnetic states of Fe nanoparticles changed from superparamagnetism to ferromagnetism with the particle size and microstructure. Oxidation heat treatment leads to the successive appearance of oxide phases.
In this work, a new model based on energy balance for heteroepitaxial growth on a patterned substrate and an additional thin buffer layer on top of it has been developed. The structure used in our model is assumed to be GeSi/buffer-Si/patterned-Si and comparisons are made with simple crystalline GeSi/Si. However, the model described here is quite general and can be adopted for any other material systems. Using this model, coupled with experimentally known material constants, the critical layer thickness (hc) of a lattice mismatched heterolayer can be determined for a patterned substrate, having a characteristic “seed pads” size (l), and a buffer layer thickness (hb). The dislocation-free condition under this case is also established.